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REFERENCE

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NBS

PUBLICATIONS

Ballistic Tests of Used Soft BodyArmor

Daniel E. Frank

U.S. DEPARTMENT OF COMMERCENational Bureau of Standards

National Engineering Laboratory

Law Enforcement Standards Laboratory

Gaithersburg, MD 20899

August 1986

Issued September 1986

Prepared for

National Institute of Justice

QC partment of Justice

2 qqjton, DC 20531

• U 5 6

86-3444

1986

NBSIR 86-3444

BALLISTIC TESTS OF USED SOFT BODYARMOR

Research Information Center

Aational Bureau of Standards

Gaithersburg, Maryland 20899

Ai 8S£-

Q-C/ do

i U-

/TO. % -5

ACKNOWLEDGMENTS

This report was prepared by the Law Enforcement Standards Laboratory of the

National Bureau of Standards under the direction of Lawrence K. Eliason, Chief of LESL.

The National Institute of Justice Technology Assessment Program (TAP) Information Center

awarded the contract and monitored the ballistic testing described in this report, which

was conducted by H. P. White Laboratory, Inc., Street, MD 21154. Mr. Brad Stimson,

National Research Council of Canada, Public Safety Project Office, participated in the

test design and witnessing of the actual testing. The contributions of Marc Caplan, TAP

Information Center are likewise acknowledged. The research was sponsored by the

National Institute of Justice, Lester D. Shubin, Standards Program Manager. The

technical effort to develop this report was conducted under Interagency Agreement

LEAA-J-IAA-021-3 , Project No. 7101.

,

.

*

FOREWORDI

The Law Enforcement Standards Laboratory (LESL) of the National Bureau of Standards

(NBS) furnishes technical support to the National Institute of Justice (NIJ) program to

strengthen law enforcement and criminal justice in the United States. LESL's function

is to conduct research that will assist law enforcement and criminal justice agencies in

the selection and procurement of quality equipment.

LESL is: (1) Subjecting existing equipment to laboratory testing and evaluation

and (2) conducting research leading to the development of several series of documents,

including national voluntary equipment standards, user guides and technical reports.

This document presents the results of a joint NIJ and National Research Council

( NRC ) of Canada effort to evaluate the effect of age upon the ballistic-resistant

capabilities of police body armor. The testing program was administered by the NIJ

Technology Assessment Program Information Center assisted by LESL in support of NRC and

NIJ.

Technical comments and suggestions concerning this document are invited from all

interested parties. They may be addressed to the author or to the Law Enforcement

Standards Laboratory, National Bureau of Standards, Gaithersburg, MD 20899.

Lawrence K. Eliason, Chief

Law Enforcement Standards Laboratory

iii

CONTENTS

Page

Foreword iii

1. Introduction 1

2 . Background 2

3. Ballistic Resistance Test Methods 4

4. Test Specimens 6

5. Test Results 9

6. Discussion 16

7. Conclusions 19

8. References 20

Appendix A—

V

5QBallistic Limit Test Data, Seven Layer Kevlar Soft Body Armor,

38 Caliber, 158 Grain, Lead Round Nose Projectile 21

Appendix B--V5Q

Ballistic Limit Test Data, Seven Layer Kevlar Soft Body Armor,

22 Caliber, 40 Grain, Lead Round Nose Projectile 28

v

COMMONLY USED SYMBOLS AND ABBREVIATIONS

A ampere H henry nm nanometerac alternating current h hour No. numberAM amplitude modulation hf high frequency o.d. outside diametercd candela Hz hertz (c/s) Cl ohmcm centimeter i.d. inside diameter P- pageCP chemically pure in inch Pa pascalc/s cycle per second ir infrared pe probable error

d day J joule pp. pages

dB decibel L lambert ppm part per milliondc direct current L liter qt quart°C degree Celsius lb pound rad radian

°F degree Fahrenheit lbf pound-force rf radio frequency

diam diameter lbf-in pound-force inch rh relative humidity

emf electromotive force lm lumen s second

eq equation In logarithm (natural) SD standard deviationF farad log logarithm (common) sec. sectionfc footcandle M molar SWR standing wave radiofig- figure m meter uhf ultrahigh frequencyFM frequency modulation min minute uv ultravioletft foot mm millimeter V voltft/s foot per second mph mile per hour vhf very high frequency

g acceleration m/s meter per second W wattg gram N newton X wavelengthgr grain N-m newton meter wt weight

area= unit2 (e.g., ft2 , in 2 , etc.); volume= unit 3 (e.g., ft 3 , m J, etc.)

PREFIXES

d deci (10'1

)da deka (10)

c centi ( 10'2) h hecto (10

2

)

m milli (10-3) k kilo (103)P micro (10*

6) M mega (106)

n nano (1C)'9) G giga (109 )P pico (10

12) T tera (10

12)

COMMON CONVERSIONS(See ASTM E380)

ft/s X 0.3048000= m/sft X 0.3048=mft-lbfX 1.355818= Jgr X 0.06479891 =gin X 2.54= cmkWhx3 600 000= J

lbx0.4535924= kgIbfx 4.448222 = Nlbf/ftX 14.59390= N/mlbf-mX 0.11 29848 = N-mlbf/in

2 X 6894.757 = Pamph X 1 .609344 = km/hqtX 0.9463529= L

Temperature: (T-f-32)X 5/9= T-c

Temperature: (T-c X 9/5)+ 32 = T-p

vi

Ballistic Tests of Used Soft Body Armor*

Daniel E. Frank

National Bureau of StandardsGaithersburg, MD 20899

A sample of 24 ballistic resistant undergarments (soft body armor) from a

production lot of 1500 originally distributed to 15 police departments

throughout the United States in 1975 for issue to officers as part of a Law

Enforcement Assistance Administration demonstration project, was tested for

V5Q

ballistic limit. The program was a joint effort of the U.S. Department of

Justice National Institute of Justice and the National Research Council of

Canada Public Safety Project Office. Tests of ballistic limit were conducted

on virgin armor that were never issued, and armor showing evidence of light,

moderate, and heavy wear both dry and while wet. The results show that armor

does not lose ballistic efficiency as a consequence of age.

Key words: ballistic limit; ballistic-resistant body armor; ballistic

testing; body armor; Kevlar; soft body armor

1 . INTRODUCTION

1

Soft body armor suitable for routine full time use by police officers became

available in quantity in the mid 1970 's following development by the National Institute

of Justice (NIJ), previously the National Institute of Law Enforcement and Criminal

Justice of the Law Enforcement Assistance Administration. In the interim, soft body

2armor manufactured from Kevlar aramid fiber fabric has gained widespread use. While

*Law Enforcement Standards Laboratory, National Engineering Laboratory.

1The use of trade names in this report does not constitute endorsement by the

National Bureau of Standards, the U.S. Department of Justice, or any other governmentagency; nor does it imply that a product is necessarily best suited for the intendeduse

.

2Registered trade name of E. I. Du Pont de Nemours & Co., Inc.

1

exact statistics are not available it is estimated that more than 50 percent of the

nation's police have been issued body armor, or have purchased it themselves.

Many police departments are currently continuing to use armor that was purchased

prior to 1975. Although there has never been a reported incident of armor manufactured

from Kevlar failing to protect an officer when assaulted with a weapon having a

ballistic threat equal to or less than the rated protection of the armor, those

departments with older armor are increasingly concerned with the effect of age and wear

upon Kevlar fabric.

During the last year, the NIJ Technology Assessment Program (TAP) Information

Center, and the National Research Council of Canada (NRC) Public Safety Project Office

have received numerous inquiries from police agencies questioning whether it is

necessary to replace older existing armor to be sure that their officers are properly

protected. In response to these questions, NIJ and NRC requested that the National

Bureau of Standards Law Enforcement Standards Laboratory ( LESL ) collaborate with the TAP

Information Center to conduct tests of soft body armor that had been in service for

extended periods of time. The discussion that follows describes the testing program

that was conducted and presents the results of this effort.

2 . BACKGROUND

The NIJ, aware of the rapidly increasing number of officer fatalities through

handgun assault during the late 1960's and early 1970 's recognized that the physical

properties of Kevlar held potential for ballistic resistance. Preliminary experiments

demonstrated that Kevlar was highly efficient in ballistic resistance and NIJ launched

an effort to develop soft body armor that was suitable for routine full time use by

police officers.

The objective of the development effort was to design armor that would protect

officers from the most common handgun threats of that time, the 38 caliber bullet at a

velocity of 850+50ft/s, and the 22 caliber bullet at a velocity of 1050+50 ft/s.

Experiments were conducted to determine the minimum number of layers of Kevlar required

2

to provide the desired ballistic protection, and it was found that seven layers were

suitable. Since Kevlar fabric was not available in commercial quantity at the time, NIJ

awarded contracts to several weavers to produce large quantities of the fabric.

Following this, NIJ awarded contracts to several manufacturers to produce

ballistic-resistant undergarments in accordance with the NIJ design specification. A

total of 3000 such garments of two designs were manufactured, together with 2000

additional garments of several other types of soft body armor.

In order to prove that the new armor was effective in protecting the officers from

handgun assault, and that it was suitable for full time routine use throughout the

United States, NIJ distributed the armor to 15 cities throughout the United States. The

resulting field test verified that all of the objectives of the NIJ development effort

3had been met [1] , and body armor manufacturers began to actively market the new armor.

During the time that NIJ developed the new soft body armor, LESL developed a

performance standard for body armor, which was promulgated by NIJ as a voluntary

national standard in 1973. Since then, the NIJ standard, which has been revised twice

to remain current with technology, has been widely used both domestically and

internationally as the basis upon which body armor is purchased.

During the course of its development effort, NIJ was careful to document the

details of the experimental effort. Thus, data were available concerning the

ballistic-resistant characteristics of the original production lots that would enable

valid conclusions concerning the effect, of age and wear, if any, upon the ballistic

efficiency of those vests if samples could be obtained for laboratory tests.

The TAP Information Center contacted each of the 15 cities that had been given

undergarments during the NIJ demonstration program and requested a search of property

records to determine if any of the vests were still in their possession. In addition,

NIJ examined its own property records and requested that other Federal agencies that

purchased armor in parallel with the NIJ program do the same.

3Numbers in brackets refer to references in section 8 of this report.

3

Five cities located armor from the original NIJ purchase, some still in actual use

and some in inventory. Similarly, NIJ and two other Federal agencies were able to

locate armor manufactured at that time, some of which was never worn.

3. BALLISTIC RESISTANCE TEST METHODS

The physical characteristics of Kevlar fiber, and the fabric woven from it, vary

somewhat from lot to lot and even within a lot, as with any item of manufacture. As a

consequence, when multiple layers of fabric are used to construct soft body armor the

ballistic resistance of individual vests of the same design varies from one to another.

The NIJ standard for ballistic resistant police body armor establishes minimum

performance requirements. To this end, body armor is tested by firing specific types of

bullets against armor samples using closely controlled velocities. Armor that is not

penetrated by the required test rounds and does not deform more than 1.73 in upon impact

is considered to meet the requirements of the standard. Because soft body armor

manufactured from fabric is known to lose ballistic efficiency when it is wet, and since

officers do get wet, the armor model is tested both dry and while wet.

The NIJ standard for body armor can be used as the basis for tests to determine

whether armor complies with the minimum performance requirements as specified, but the

test results do not provide a knowledge of the ultimate ballistic protection that a

given sample of body armor may provide. Frequently manufacturers will incorporate more

layers of fabric than required for minimum performance to ensure that the armor will

meet the ballistic requirements even if a given lot of fabric is slightly less

ballistically efficient than normal.

In order to examine the relative ballistic performance of armor, rather than simply

verifying minimum performance, it becomes necessary to use a different method of test.

The armor industry has typically used the ballistic limit as the means of comparing

the ultimate performance of armor materials.

4

V50

ballistic limit is the velocity at which a specific projectile (bullet) is

expected to penetrate the armor half of the time.

The ballistic limit of armor is most frequently conducted using the procedures of

MIL-STD-662D [2]. Essentially, the specified test projectile is fired at the armor over

a range of impact velocities and the specimen examined after each impact to determine

whether the projectile has penetrated the armor or not. While the standard permits

different velocity ranges from the highest velocity test round to the lowest, a total

velocity range of 125 ft/s is most commonly used for the test. In practice, the first

projectile is fired at a velocity controlled so as to yield an impact velocity near that

of the expected V^q. If the first projectile penetrates the velocity of the second test

round is reduced and the impact point examined for penetration. Conversely, if the

first projectile does not penetrate, the velocity of the second round is increased and

the impact point examined for penetration. The objective is to fire a total of 10

projectiles at various velocities to obtain 10 impacts; five of which penetrate and five

of which do not within an overall velocity range of 125 ft/s. The ballistic limit

is then calculated as the average velocity of the 10 test rounds.

The test results presented in this report were obtained using the procedures of

MIL-STD- 6 6 2D.

The NIJ standard for police body armor requires the evaluation of both the

penetration resistance of body armor and the deformation of the armor caused by the

bullet impact. The deformation, which is measured as the depth of the indentation in

the clay backing material at the point of a nonpenetrating impact, is determined to

ensure that an individual wearing the armor will be protected from blunt trauma.

Specifically, NILECJ-STD-0101 . 01 , Ballistic Resistance of Police Body Armor [3]

(the test method used to obtain some of the results presented in this report) requires

that the deformation not exceed 1.73 in for Type I armor when impacted with a 40 grain

lead round nose 22 caliber bullet at a velocity of 1050+50 ft/s and a 158 grain lead

round nose 38 caliber bullet at velocity of 850+50 ft/s.

5

The deformation measurements were included in the experimental design to determine

whether deformation might be an early indicator of ballistic deterioration, should used

armor exhibit a significant loss in ballistic efficiency.

4 . TEST SPECIMENS

The 24 sets of body armor tested in this program were all of the same design as

shown in figures la and lb and the vests were constructed of seven layers of 1000

2denier, 31x31 plain weave Kevlar fabric, which was waterproofed with Zepel D .

Figure la. Front of vest outside and inside.

6

Figure lb. Back of vest outside and inside.

During manufacture, the two outer layers of Kevlar fabric and the exterior cover

were cut to the finished size. The five interior layers were cut slightly smaller than

the outer layers. The interior Kevlar layers were first stitched together at a number

of points near the edge of the fabric. The interior layers were then placed between the

two outer Kevlar layers and the front cover and the assembly was completed by sewing

bias tape around the entire edge attached to the outer Kevlar layers, which extended

approximately one-half inch beyond the edge of the interior layers.

The back panel construction was identical to that of the front panel as described

above; however, in addition, the back panel was reinforced by vertical stitching from

top to bottom at intervals of approximately 4 in from one side to the other.

Each vest was clearly labeled "LEAA Prototype Protective Garment," which enabled

verification that the garment was indeed from the original LEAA demonstration production

lot.

While the property records of the five police departments were sufficiently

accurate to locate the test specimens, it was generally not possible to obtain accurate

information concerning the wear and maintenance details for the individual vests. This

was a consequence of the fact that the individuals that were issued the vests were no

longer on their respective forces and efforts to locate the officers were unsuccessful.

It was possible to obtain limited use information for only seven of the vests.

Five of the vests (15, 17, 18, 20, and 21) were obtained from a department with a very

hot, moderately humid climate. These vests were issued upon receipt from LEAA in 1975

and were still in service when recalled for testing in April 1986--a service period well

over 10 years. The department policy was one of voluntary use, however, the department

believes that the officers that wore the vests did so full time except for the hottest

months of the summer.

Vest 6 which came from a department with a generally hot, humid climate, was worn

by three different officers. The first officer had the vest for over a year and

one-half; however, its use was not known. The second officer wore it full time while on

duty for approximately two years, wiping it with a damp sponge and soap and never

machine washing it. The last officer wore it for a one-year period but the extent of

wear is not known.

Vest 9 which came from a department with a very hot humid climate, was used by the

first officer of issue for over three and one-half years. There is no information on

the extent of use. The vest was subsequently issued to an auxiliary officer that wore

it full time while on duty for a period of five years. However, this officer was only

on duty a few days each month.

In the absence of detailed use information, it became necessary to rely upon visual

inspection to estimate the extent of use. Eight of the 24 test specimens were unused.

Representatives of NIJ, LESL, and the TAP Information Center examined each of the

remaining 16 specimens that had been used. It was possible to separate the vests into

three groups;

o Four exhibited light wear

o Four exhibited moderate wear

o Eight exhibited heavy wear

8

Once the test specimens were classified in accordance with use (unused, light wear,

moderate wear, heavy wear), they were randomly assigned to two test groups. One group

was scheduled for ballistic test using 38 caliber ammunition, the other for tests using

22 caliber ammunition. Finally, half of the vests in each group were scheduled for

ballistic tests while wet and the other half for ballistic tests while dry.

5 . TEST RESULTS

The testing of used armor was conducted by the H. P. White Laboratory, Inc.,

Street, Maryland, during the period from May 22 to June 10, 1986. Representatives of

the TAP Information Center, the National Research Council of Canada, and LESL witnessed

all testing.

The test samples were mounted at a distance of 16.0 ft from the test weapon on clay

backing as specified by NILECJ-STD-0101 . 01 to produce a zero degree angle of obliquity.

The first shots on each panel were to determine the back face signature (clay

deformation) in accordance with NILECJ-STD-0101 . 01 after which the V^q of the panel was

determined. Light screens were positioned at 6.5 and 9.5 ft which, in conjunction with

an elapsed time counter (chronograph), were used to determine all bullet velocities at

8.0 ft.

In conducting ballistic limit tests of the 24 samples, the front and back panels of

each vest were tested separately. Every effort was made to obtain 10 valid impacts for

the determination of V^q ballistic limit. However, there were a number of instances in

which the shot placement was such that it was not possible to obtain 10 valid impacts

and, in these cases, 8 shot ballistic limit data are reported. Similarly, there

were instances in which the inspection of the vest at a later date revealed that an

impact used to calculate a 10 shot V^q ballistic limit was not a valid impact and the

data was recalculated on the basis of an 8 shot V,-q.

Table 1 summarizes the ballistic limit for each vest tested using 38 caliber

bullets. Following completion of the tests, vest 22 was reinspected and found to

contain eight layers of Kevlar, rather than the specified seven layers. Table 2

9

presents the blunt trauma deformation measurements that were obtained using 38 caliber

bullets.

Table 1. V,.q ballistic limit data,38 caliber, 158 grain, lead round nose bullet

(V^q expressed in feet per second)

Unused vests Light wear vests Moderate wear vests Heavy wear vests

Sample V50

Sample V50

Variationfrom unusedvest average(percent) Sample V

50

Variationfrom unusedvest average(percent) Sample

Variationfrom unusedvest average

V5Q

(percent)

IF 1074 33F 1104 +3.2 10F 1108 +3.6 17F 1153 +7.8

IB 1075 33B 1135 +6.1 10B 1165 +8.9 17B 1075 +0.5

23F 1036 12FC

1126C

+5.2 30FC

1120 +4.7 31F 1131 +5.7

24B 1050 12BC

1 1 12c

+3.9 30BC

1118 +4.5 31B 1152b

+7.7

4FC

1088 Average 1119 +4.6 Average 1128 +5.4 18FC

1080 +0.9

4BC

1095 18BC

1074 +0.4

Average 1070 13FC

1 1 59b

+8.3

22Fa,C

1 16 la

13BC

1129b

+5.5

22Ba,C

1193 Average 1119 +4.6

aSample 22 contained eight layers of fabric, excluded from average.

bEight shot Vj-q determination.

CTested wet.

10

Table 2. Deformation measurements, 38 caliber projectile

Unused vests Light wear vests

Sample

AverageImpact

Velocity(ft/s)

Defor-mation(in) Sample

AverageImpact

Velocity(ft/s)

Defor-mation(in)

IF 895 1.65 33F 880 1.40

887 1.50 893 1.40

IB 850 1.60 33B 874 1.50

877 1.45 888 1.35

23F 867 1.50 12Fa

892 1.45

884 1.50 897 1.50

24B 895 1.50 12Ba

842 1.70871 1.60 823 1.65

4Fa

888 1.60

866 1.60

4Ba

867 1.60

869 1.60

22Fa

896 1.60875 1.40

22Ba

881 1.30

902 1.45

aTested wet.

Moderate wear vests Heavy wear vests

Sample

AverageImpact

Velocity(ft/s)


AverageImpact

Velocity(ft/s)

Defor-mation(in)

10F 855 1.50 17F 860 1.50885 1.60 872 1.60

10B 885 1.60 17B 867 1.50898 1.45 889 1.30

30Fa

837 1.45 31F 875 1.45839 1.65 881 1.50

30Ba

854 1.40 31B 877 1.35837 1.60 885 1.50

18Fa

872 1.60877 1.60

18Ba

882 1.65882 1.50

13Fa

821 1.50

828 1.60

13Ba

837 1.50834 1.55

Note: All velocity measurements rounded to nearest foot per second.

Table 3 summarizes the V^q ballistic limit for each vest tested using 22 caliber

bullets, and table 4 presents the blunt trauma deformation measurements obtained with 22

caliber bullets.

11

Table 3. V,.q Ballistic Limit Data.22 caliber, 40 grain, lead round nose bullet

(V^q expressed in feet per second)

Unused vests Light wear vest Moderate wear vests Heavy wear vests

Sample V50

Sample V50


50


50

Variationfrom unusedvest average(percent)

2F 1179 15F 1219 +1.6 32F 1238 +3.2 20F 1160 -3.3

2B 1203 15B 1267 +5.6 32B 1224 +2.0 20B 1172 -2.3

25F 1200 21Fb

1214 +1.2 7Fb

1183 -1.4 8F 1200 0

25B 1217 21Bb

1239 +3.3 7Bb

1251 +4.3 8B 1205 +0.4

3Fb

1169 Average 1235 +2.9 Average 1224 +2.0 9F 1183 -1.4

3Bb

1164 9B 1154 -3.8

26Bb

1260 6F 1182 -1.5

27Fb

1210 6B 1137a

-5.3

Average 1200 Average 1174 -2.2

Dry retest. Initial wet test,not included not includedin average in average

3F 1102 9Fb

1183 -1.4

3B 1182 9Bb

1099 -8.4

6Fb

1075a

-10.4

6Bb

1 145a

-4.6

aEight shot determination.

^Tested wet.

12

Table 4. Deformation measurements, 22 caliber projectile

Unused vests Light wear vests

Sample

AverageImpact

Velocity(ft/s)


AverageImpact

Velocity(ft/s)

Defor-mation(in)

2F 1064 0.80 15F 1054 0.801063 0.85 1115 0.90

2B 1096 0.90 15B 1101 0.551063 0.85 1083 0.60

25F 1077 0.85 21Fa

1058 0.801054 0.80 1083 0.85

25B 1051 0.80 21Ba

1066 0.801070 0.85 1066 0.75

3Fa

1049 0.851071 0.95

3Ba

1071 0.751103 0.80

26Ba

1083 0.751073 0.70

27Fa

1101 0.851038 0.751064 0.75

Moderate wear vests Heavy wear vests

Sample

AverageImpact

Velocity(ft/s)


AverageImpact

Velocity(ft/s)

Defor-mation(in)

32F 10291085

0.900.85

20F 10751067

0.700.65

32B 1066

1068

0.800.80

20B 10571063

0.800.70

7Fa

10541085

0.800.80

8F 1058

1081

0.850.75

7Ba

1040

10380.800.85

8B 10401081

0.750.25

9Fa

1059

1053

0.200.75

9Ba

1095

1060

0.800.80

6Fa

1054

1049

b

b

6Ba

1068

10850.800.65

aTested wet.

^No measurement, test round penetrated armor.

Note: All velocity measurements rounded to nearest foot per second.

Table 5 expands upon the ballistic limit data summarized in table 1, to include the

velocity of the highest velocity nonpenetrating round (H ), the velocity of the lowestP

velocity complete penetration round (Lc )

and the velocity range of mixed results of

penetrating and nonpenetrating rounds for 38 caliber bullets.

13

Table 5. Complete ballistic limit data, 38 caliber

Unused vests

Sampleno

.

V50

( ft/s)

HP

( ft/s)

Lc

(ft/s)

Rangemixed(ft/s)

IF 1074 1113 1031 82IB 1075 1073 1075 N/A

23F 1036 1083 988 9524B 1050 1079 1036 434F

a1088 1109 1064 45

4Ba

1095 1087 1105 N/A

22Aa 1161 1147 1170 N/A22B

a 1193 1238 1149 89

Light wear vests

Sampleno

.

V50

( ft/s)

HP

(ft/s)

Lc

(ft/s)

Rangemixed( ft/s)

33F 1104 1181 1062 11933B 1135 1167 1111 56

12Fa

1126 1113 1113 012B

a1112 1097 1095 2

Medium wear vests

Sampleno.

V50

(ft/s)

HP

( ft/s)

Lc

(ft/s)

Rangemixed(ft/s)

10F 1108 1163 1091 7210B 1165 1220 1101 119

3 0Fa

1120 1165 1093 723 0B

a1118 1138 1093 45

Heavy wear vests

Sampleno.

V50

(ft/s)

HP

(ft/s)

Lc

(ft/s)

Rangemixed(ft/s)

17F 1153 1163 1154 917B 1075 1107 1062 4531F 1131b 1174 1060 11431B 1152

b1208 1132 76

18F 1080 1097 1064 3318B

a1074h 1097 1062 35

13Fa H59b 1222 1158 64

13B 1129° 1210 1103 107

aTested wet.

bEight shot Vj-q.

Table 6 expands upon the ballistic limit data summarized in table 3,

Lc ,

and range of mixed velocities for 22 caliber bullets.

including Hp,

14

Table 6. Complete ballistic limit data, 22 caliber

Unused vests Medium wear vests

Sampleno

.

V50

( ft/s)

HP

( ft/s)

Lc

( ft/s)

Rangemixed(ft/s)

Sampleno.

V50

(ft/s)

HP

( ft/s)

Lc

( ft/s)

Rangemixed(ft/s)

2F 1179 1202 1165 37 32F 1238 1268 1215 532B 1203 1238 1188 50 32B 1224 1258 1192 66

25F 1200 1245 1174 71 7F 1183 1156 1154 0225B 1217 1255 1176 79 7B

a1251 1261 1230 31

3Fa 1169 1176 1152 24

3Ba 1164 1195 1143 52

26Ba 1260 1288 1232 56

27Fa 1210 1238 1160 78

Retest (Dry)

3F 1102 1085 1085 03B 1182 1220 1170 50

Light wear vests Heavy wear vests

Sampleno

.

V50

(ft/s)

HP

( ft/s)

Lc

(ft/s)

Rangemixed(ft/s)

Sampleno.

V50

(ft/s)

HP

(ft/s)

Lc

(ft/s)

Rangemixed( ft/s)

15F 1219 1220 1220 0 20F 1160 1147 1145 215B 1267 1290 1260 30 20B 1172 1174 1172 221F

a1214 1242 1198 44 8F 1200 1222 1176 46

21Ba 1239 1248 1240 8 8B 1205 1220 1195 25

9F 1183 1181 1154 279B

a1099 1147 1075 72

6Fa 1075° 1091 1049 42

6B 1145° 1172 1115 57

Retest (Dry)

9F 1183 1198 1160 389B 1154 1178 1136 426F 1182 1192 1155 376B 1137° 1165 1143 22

£Tested wet.

bEight shot V^q.

Appendix A presents the raw data for each sample that was tested using 38 caliber

projectiles, noting the impact velocity of each bullet that was fired to determine the

V^q ballistic limit, whether or not it penetrated, and identifies those test rounds used

to calculate the V5Q

ballistic limit. Test rounds associated with deformation testing

(see tables 2 and 4) are not included. Appendix B presents the same penetration data as

appendix A but for 22 caliber projectiles under the same limitations as appendix A.

15

Those test rounds reported in appendix A and B that were not used to obtain the V CrtoO

ballistic limit were excluded from calculation for a variety of reasons, including 1)

hitting too close to an edge or prior hit, 2) projectile yaw, and 3) outside of the

desired maximum velocity range.

6. DISCUSSION

When tested following the procedures of NILECJ-STD-0101 . 01 , the deformation

measurements that were made for all samples were well within the specified maximum limit

of 1.73 in. There was no apparent difference between dry testing and wet testing. From

these tests we concluded that impact deformation does not appear to hold promise as an

early indicator of loss of ballistic resistant efficiency.

The interpretation of the V^q ballistic limit data for the vests that were

evaluated can be considered somewhat subjective because the data are too limited to

permit rigorous statistical analysis. However, the following was derived from this

series of tests.

The average V^q ballistic limit for the 38 caliber test rounds of the 10 year old

unused armor is 1070 ft/s, excluding vest 22, which consists of eight layers of Kevlar.

The standard deviation of the V,-0

is 22.6 ft/s, with an overall range of 59 ft/s. There

is no obvious difference within any of the four wear groups (new, light wear, moderate

wear, or heavy wear) between tests conducted with the armor wet or dry.

When the V5Q

ballistic limit of each of the used vests is compared to the average

of the unused vests of the same construction, in all cases the used vest has a higher

V50

*

When the average V5Q

of the three used vest groups (wet and dry testing avenged

together) is compared with that of the unused armor, each of the three used vest groups

exhibit V5Q

roughly 5 percent higher.

16

V^0ballistic limit data for the 158-grain lead round nose bullet was not reported

in testing conducted by Edgewood Arsenal during the earlier LEAA development effort;

however, partial data [4] imply a V5Q ballisticlimit on the order of 1000 ft/s. Since

the tests were conducted with fabric not sewn together, one would expect a higher V5Q

for the finished vests that were tested, and the values of V,-0ballistic limit that were

obtained are consistent with the earlier data.

It is perhaps of more interest to examine the test results in terms of the velocity

of the lowest complete penetration for each panel, for this gives a better idea of

absolute ballistic resistance relative to the rated threat level. The test velocity for

the determination of penetration for a Type I vest is 850+50 ft/s, or a maximum velocity

of 900 ft/s. With one exception, all of the vests that were tested demonstrated a

velocity for the lowest velocity complete penetration more than 150 ft/s above that

required for minimum performance. Even the poorest performing armor sample (vest 23

front) exceeded the 900 ft/s requirement by a velocity of 88 ft/s.

As with the 38 caliber testing of V5Q

ballistic limit, there did not appear to be

any overall difference between 22 caliber tests conducted wet and dry, other than

discussed below. The overall average V^q ballistic limit using the 22 caliber 40 grain

lead round nose bullet was 1200 ft/s with a standard deviation of 31 ft/s and an overall

range of 96 ft/s. Earlier data from Edgewood Arsenal [3] reports a ballistic limit

for seven layers of Kevlar 1000 denier fabric of 1084 ft/s. Again, these tests used

fabric only and the ballistic limit of the fabricated vests would be expected to exceed

that reported. The same Edgewood report presents a V,-q ballistic limit of seven layers

of 1140 denier Kevlar of 1213 ft/s. This fabric is similar to 1000 denier in ballistic

efficiency, although, it was not treated for water repellency. Since the overall

ballistic efficiency of treated Kevlar is known to be less than untreated, the average

V,-q of 1200 ft/s is reasonable for the unused armor that was tested in this program.

When first tested wet, the front panel of vest 6 was penetrated at velocities of

1054 and 1049 ft/s and the V^q ballistic limit was 1075 ft/s; well below the 1100 ft/s

upper limit of threat Type I protection (1050+50 ft/s). Likewise, the V5Q

ballistic

limit of the back panel of vest 9 was 1099 ft/s which is marginal performance at best.

Since all other vests tested with 22 caliber bullets were found to have V^0

ballistic

17

limits well in excess of 1100 ft/s, the data for vests 6 and 9 were suspect. Similarly,

vest 3, also tested wet, appeared to have a somewhat low V5Q ballistic limit, when

compared to the other unused vests.

Vests 3, 6, and 9 were allowed to dry in a well ventilated, controlled environment

for several days, and once feeling dry to touch, were retested dry for ballistic limit

using the 22 caliber ammunition. The two panels in most question, 9B and 6F, when

retested dry, demonstrated V^q ballistic limits well above 1100 ft/s, as did the lowest

velocity complete penetrating rounds. The other parts of these vests continued to

demonstrate satisfactory V^q ballistic limit and lowest complete penetrating velocity,

when dry.

The retest of vest 3 was not conclusive. The V^q ballistic limit of the back panel

increased slightly when retested; however, that of the front panel decreased. While the

placement of the bullet impacts during retest were sufficiently distant from prior

impact locations to constitute fair hits, it remains possible that the previous testing

prevented obtaining valid data in the second set of tests (see fig. 2).

Figure 2. Front of vest 3 after being shot.

18

Overall, as with the 38 caliber testing, the ballistic limit of the light and

moderate wear samples tested with 22 caliber bullets increased when compared with the

average of the unused samples. The heavily worn vests had an average V^q ballistic

limit of 1174 ft/s (using data for vest 6 and 9 tested dry), 2.2 percent less than the

average 1200 ft/s ballistic limit of the unused vests.

7 . CONCLUSIONS

Body armor manufactured from Kevlar fabric retains full ballistic efficiency when

stored under typical warehouse conditions for periods of time in excess of 10 years. It

may well be, as anticipated, that such armor has an unlimited shelf life.

Deformation measurements using wet or dry armor do not appear to provide

significant information as a means of identifying decreased ballistic efficiency of used

armor manufactured from Kevlar fabric.

Two of the sample vests that were tested for ballistic limit did not appear to have

adequate waterproofing. It is not known whether this was a consequence of heavy wear or

improper water repellent treatment at the time of manufacture.

Both the 38 caliber and 22 caliber ballistic limit data support an apparent trend

of improved ballistic efficiency as a consequence of light to moderate wear and possibly

a slight decrease in ballistic efficiency as a result of heavy wear. The limited data

that were obtained and the variation of ballistic efficiency within lots of Kevlar

fabric is such that it is very difficult to say with certainty that the difference

between the Vj-q of unused and heavily used vests is solely a consequence of wear, or due

to the individual samples. Recent data obtained from the U.S. Army [5] for V5Q

ballistic limit of 16 production lots of Kevlar fabric (12-layer test samples tested

using the 22 caliber fragment simulator) demonstrate ranges of V5Q

ballistic limits of

more than 6 percent between individual lots.

The possible trend of decreased ballistic efficiency of armor following heavy use,

coupled with the identification of at least two armor panels that lacked waterproofing.

19

strongly suggest that it is prudent for any police department to inspect the vests worn

by its officers on at least an annual basis. Representative samples of vests showing

extremely heavy wear should be tested for ballistic performance. Such tests should be

conducted with the vests in the wet condition. In the interest of minimizing testing

cost, it is recommended that such testing be limited to the six shot test sequence

specified by the current edition of the NIJ Standard using a single test round (22

caliber for Type I vests and 9 mm for Level IIA, II, and IIIA vests).

8 . REFERENCES

[1] Body armor field test and evaluation final report. Vol. I, Executive Summary.

Aerospace Corporation, Law Enforcement and Telecommunications Division, Washington,

DC; 1977 September.

[2] Ballistic test for armor. Military Standard MIL-STD-662D. U.S. Army Materials and

Mechanics Research Center, Watertown, MA 02172; 1984 March 19.

[3] Ballistic resistance of police body armor. NILECJ-STD-0101 . 01 . National Institute

of Justice, U.S. Department of Justice, Washington, DC 20531; 1978 March.

Superseded by NIJ Standard-0101.02, Ballistic Resistance of Police Body Armor dated

March 1985.

[4] Prather, R. N. , Swain, C. L. , Hawkins, C. E. Back face signatures of soft body

armors and the associated trauma effects. RCSL-TR-77-55 . Chemical Systems

Laboratory, Aberdeen Proving Ground, MD; 1977 November.

[5] Personal communication with the Defense Personnel Support Center, Philadelphia, PA.

20

APPENDIX A

Vj-q Ballistic Limit Test Data

Seven Layer Kevlar Soft Body Armor

38 Caliber, 158 Grain, Lead Round Nose Projectile

21

Sample 1 (unused) ; tested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.

Averagevelocity(ft/s)

Roundno

.


Roundno

.


Roundno

.


4 1026 3 1143 3 1005 6 107 5a5 1081 6 1218 4 995 8 1138 a8 1077 a 7 1085 a 5 1073 a 10 1089 a

10 1081a 9 108 l a 7 906 11 lllla13 1075a 11 1064 a 9 1022 a 13 117814 1113 a 12 103 l a 12 1058 a 15 115816 1036 a 15 1097 a 14 102 6 a 16 1124 a

17 103 la

Sample 4 (unused) ; tested wet

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno

.


Roundno.


Roundno

.


4 1109 a 3 1202 4 1014 3 1143 a9 107 3 a 5 1188 5 1020 6 1156a

10 1068 a 6 1070a 8 984 7 1105 a11 1051 a 7 1 14 9 a 9 1054 a 10 llll a

12 1022 a 8 1130 a 12 1054 a 11 1130 a

13 1149 a 13 97714 1064 a 14 1054 a

15 102416 1087 a17 1058 a

aUsed to calculate V5Q ballisticlimit.

22

Sample 10 (moderate wear) ; tested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno.


Roundno.


Roundno.


3 1075a 4 104 l a 5 1077 7 12775 1163a 6 1103 a 6 1073 8 1160 a8 949 7 1132 a 10 974 9 12 08 a

9 932 11 114 l a 11 113 6a 12 1210 a10 1119 a 12 1145 a 13 1158 a 15 12 10 a13 1056a 14 1113 a 18 1101a14 1053 a 16 113 6a

17 107019 1220 a

Sample 12 (Light wear) ; tested wet

Front Back

Partial Completepenetration penetration

Roundno.


Roundno.


10 107 0 a 2 1184 a

11 1062 a 9 1174 a

12 1113 a 15 1163 a

13 1107 a 16 119214 llll a 17 1113 a

18 1165a


Roundno.


Roundno.


3 861 6 1134 a

4 1089 a 8 1165 a

5 1040 10 1095 a7 1062 a 14 1160 a9 1097 a 16 1192

11 982 17 1138a12 1085 a

13 1097 a15 964

aUsed to calculate V^q ballistic limit.

23

Sample 13 (heavy wear) ; tested wet

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno

.


Roundno.


Roundno

.


5 1103 a 4 1158 a 5 1210 a 3 11437 1124a 6 1186 a 6 113 0 a 4 1103 a8 871 9 1165 11 1085 a 7 1126 a

12 1064 11 1165 a 14 1128 a 8 117213 978 16 1235 17 1073 9 113814 1147 a 17 117 0 a 10 116315 1087 19 1215 12 115618 1222 a 13 1132 a

15 1117 a

18 118619 114320 1174

Sample 17 (heavy wear) ? tested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno

.


Roundno.


Roundno

.


3 1089 a 7 1285 6 1107 a 3 12664 1119 a 12 1232 11 1040a 4 12456 1132 a 13 1192 a 13 1007 5 12208 1107 a 14 1192 a 14 1058 a 7 12109 840 15 1215 17 1022 a 8 1083 a

10 722 16 1154 a 18 1079 a 9 122011 867 18 1186 a 19 1003 10 114917 1163 a 20 1200 a 12 1 103 a

19 1071 15 1130a16 1068 a

20 1062 a

aUsed to calculate V,-q ballistic limit.

24


Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

AverageRound velocityno. (ft/s)

Roundno.


Roundno.


Roundno

.


5 1097 a 3 1109 a 3 1060 a 5 1079 a

6 1034 a 4 1122 a 4 1066a 6 1097 a

9 103 la 7 113 0a 7 1008 a 8 107 0 a

11 997 8 1099 a 10 1097a 9 1062 a

12 102 0a 10 1014 a 11 1073 a 13 1130 a

14 1089 a 13 1154 12 995

Sample 22 (unused) ? tested wet

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno.


Roundno.


Roundno

.


3 1073 6 1261 3 1156a 5 1192 a4 1047 8 117 6 a 4 1077 7 1261a

5 1103 a 12 1120 a 6 1195 a 10 1224 a

7 992 13 12 12 a 8 1058 11 1149 a

9 1132 a 14 1227 a 9 1238 a 15 12 18 a

10 934 19 1192 a 12 109911 1079 13 1149 a

15 1085 14 111116 1132 a 16 1149 a

17 108918 1117 a

20 1147 a

aUsed to calculate V5Qballistic limit.

25

Sample 23/24 (unused) ; tested dry

Partialpenetration


(23)

Completepenetration


Partialpenetration


(24)

Completepenetration


3 950 4 1255 4 1017 a 3 11179 1062a 5 1119 5 1029a 7 1036 a

10 958 6 1034 a 6 971 8 1049 a

11 104 5 a 7 1122 9 970 10 104 5 a

14 1007 a 8 988 a 14 965 11 1083 a

16 948 12 1047 a 16 1053 a 12 1107 a17 992 a 13 1002 a 17 1079 a 13 115618 1083 a 15 1095 a 18 1005 a 15 1245

Sample 30 (medium wear) ; tested wet

Front Back


Roundno.


Roundno.


5 108 la 3 1113 a

6 1105a 4 11568 1163 a 7 10819 1165 a 10 1230

14 940 11 118417 1083 a 12 1138 a

13 1093 a

15 1152 a

16 1105 a



Roundno.


Roundno.


5 1134 a 3 1134 a

7 1138 a 4 1093 a

8 992 6 108511 1128 a 9 121013 1073 a 10 1130a

14 982 12 1172 a

16 914 15 1176 a

17 1056 a

26

Sample 31 (heavy wear) ; tested dry

Front


Average AverageRound velocity Round velocityno. (ft/s) no. (ft/s)

3 1134 a 9 12154 1002 10 1099 a

5 1174 a 11 12246 1097 a 13 1060a

7 1122 a 15 1165a

8 1105a 17 1172 a

12 998 18 118 la

14 114716 1034

Sample 3 3 (L:

Front


Average AverageRound velocity Round velocityno

.

(ft/s) no. (ft/s)

3 977 6 113 0a

4 1068 a 11 1091a5 1031 14 1124 a

7 1087 a 15 1062 a

8 1181 a 17 1138 a

9 86110 1056a

12 1101a

13 100516 1027


Back


Average AverageRound velocity Round velocityno. (ft/s) no

.

(ft/s)

4 1120 a 6 12715 1093 a 8 12807 12 08 a 9 1261

10 958 11 124515 1075 12 1195 a

16 1154 a 13 118 la

22 1010 14 124017 123018 124019 113 6 a

20 1132 a

21 1299

wear) ; tested dry

Back



3 1167 a 7 12 00a

4 1056 8 1183 a

5 1073 10 lllla

6 1122 a 14 12209 998 19 1152 a

11 1042 22 121012 107 5 a 23 1130 a

13 106415 103116 101217 104418 1126 a20 1089 a21 1053

27

APPENDIX B

V^q Ballistic Limit Test Data

Seven Layer Kevlar Soft Body Armor

22 Caliber, 40 Grain, Lead Round Nose Projectile

28


Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno

.


Roundno.


Roundno.


3 1163 a 4 1227 a 3 1200 a 8 13166 1170a 5 1210a 4 117 0 a 10 1266 a

9 lllla 7 1186a 5 1224 11 1222 a

10 1085 8 1165a 6 1141a 12 1188 a

11 1202 a 12 1178 a 7 1238 a 14 1220 a

14 1178 a 13 1190 9 1310 15 1212 a

13 117 6a

Sample 3 (unused) ; tested wet

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno.


Roundno.


Roundno.


3 1130 5 1208 a 5 1156 a 3 12384 1165a 6 1198 a 7 1158 a 4 12 02 a7 1143 a 8 1158 a 8 1195a 6 1178a9 1143 a 10 1184 a 13 1117 a 9 1202

12 117 6a 11 1152 a 14 1132 a 10 1190 a

13 1165a 11 1170 a12 1143 a


29

Sample 3 (unused) ; retested dry

Front Back


Roundno.


Roundno

.


16 1017 14 117 6 a

17 1068a 15 1145 a

18 1066a 19 1154 a

22 107 0 a 20 1109 a

23 1066 a 21 1085 a

24 108 5a


Roundno.


Roundno.


15 1158a 16 12 02 a

17 1163 a 18 128019 1181a 21 1232 a

20 1220a 22 1220a

26 1117a 23 12 18 a

25 1170 a


Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno.


Roundno.


Roundno.


3 1024 1 1054 a 3 1099 5 12884 1007 2 1049 a 4 1132 a 6 12505 108 3 a 12 1089 a 7 1172 a 9 12306 107 5 a 14 1109 a 8 1230 10 1202 a

7 109 l a 15 1060 a 15 1051 11 12088 1051 17 1113 a 12 12089 107 0 a 19 1081 13 1181 a

11 1066a 20 1124 a 14 1 1 1

5

a

13 1062 18 1 122 a

Note: Shot 10, no velocity reading.


30

Sample 6 (heavy wear) ; retested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno

.


Roundno

.


Roundno.


16 1099 17 1158 a 25 1040 21 1143 a18 1170a 19 1240 a 26 1062 22 1163 a20 1149 a 22 1190a 27 1085 a 23 120221 1145a 24 12 05 a 28 1068 a 24 1178 a23 1167 a 25 12 08 a 29 1138 a 31 1158 a26 1192 a 30 1165a

Sample 7 (moderate wear) ; tested wet

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno

.


Roundno

.


Roundno.


Roundno

.


9 1071 3 1296 6 1186 a 3 1250 a10 114 3 a 4 1274 7 1200 a 4 12 3 0 a11 1124 5 1248 a 8 1250 a 5 117612 1154 a 6 12 3 5 a 9 1250 a 11 12 99 a14 1152 a 7 1184 a 10 1261 a 12 1290 a16 1149 a 8 1154 a 13 1293 a18 1156a 13 1357

15 128217 12 58 a

aUsed to calculate ballistic limit.

31


Front Back


Roundno

.


Roundno.


3 112 6 a 7 13274 1134 a 8 12685 1186a 9 124 5 a

6 12 15 a 10 12 3 2 a

11 1222 a 12 12 4 5a

13 1220 a

14 117 6a


Roundno.


Roundno.


3 1200 a 6 1205 a4 1220 a 7 12 15 a5 1172 11 12 15a

8 1210 a 12 12 2 0 a9 118 la 13 1195a

10 1186a


Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno

.


Roundno

.


Roundno.


4 117 6 a 3 1154 a 4 1147 a 3 11747 1158a 5 12 02 a 9 104 9 a 5 11708 1181 a 6 1165 11 1107 a 6 1145

10 1174 a 9 117 0 a 13 1101 a 7 1113 a

12 1165 a 11 1188 a 15 1000 8 110513 1202 16 109 3 a 10 1075a

14 1258 a 12 1119 a

14 1085a

16 1093 a

aUsed to calculate V5Q ballisticlimit.

32

Sample 9 (heavy wear) ; retested dry

Front Back


Roundno.


Roundno.


16 1134 a 15 1188 a17 1192 a 19 1215a

18 1198 a 20 1195a22 1149 a 21 1160 a23 1174 a 24 1227 a


Roundno.


Roundno.


18 1178 a 17 120022 1138 a 19 1186 a23 1140a 20 117 6 a26 113 0a 21 1136a27 1143 a 24 1156 a

25 1156 a

Sample 15 (Light wear) ? tested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno.


Roundno.


Roundno

.


8 1128 4 1313 3 1186a 5 12859 1205a 5 1310 4 12 02 a 6 1364

10 118 l a 6 1277 7 1280a 8 13 10 a12 1186 7 1230a 10 1290a 9 1299 a13 1215 a 11 1230 a 14 1245 a 11 133315 1190 a 14 1261 a 12 1261a

19 1220 a 16 1277 13 1304 a17 1220 a 15 1293a18 1240 a


33


Front

Partialpenetration

Completepenetration

AverageRound velocity Round

Averagevelocity

no. (ft/s) no. (ft/s)

3 1220 4 12328 1109 a 5 1232 a9 1149 6 12 08 a

10 1126 7 1145 a12 1134 a 11 1160 a13 1134 a 14 12 08 a15 1147 a

Sample 21 (light

Front


Average AverageRound velocity Round velocityno

.

(ft/s) no. (ft/s)

3 1077 6 1242 a

4 1160 a 10 1232 a

5 12 3 2 a 11 1248 a

7 1222 12 12528 1235 13 1222 a

9 1242 a 14 1198 a

15 1174 a

16 1188 a

Back



4 1147 a 3 1174 a

5 1174 a 6 1178 a

8 1160 a 7 1195 a9 117 0a 10 1198 a

12 1147 a 11 1172 a

,r) ; tested wet

Back



3 1220 a 8 1268 a

4 1250 10 1261 a

5 1238 12 124 0a

6 1261 14 12427 12 32 a 16 13279 1248 a 17 1224

11 1232 18 1264 a

13 1224 a 19 1252 a

15 119820 118 l a

aUsed to calculate V5Q

ballistic limit.

34


Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno.


Roundno

.


Roundno.


4 1212 a 3 12 12 a 6 1130 3 1258 a

7 12 08 a 5 1188 7 1113 4 1184 a

11 1245a 6 1242 8 1174a 5 117 6 a

15 117 0a 8 1304 9 1230a 12 1218 a

18 1122 a 9 1261 10 1198a 14 1282 a10 1250 11 1198 a

12 12 02 a 13 12 55a

13 1190a14 1238 a

16 127717 1174 a

Sample 26/27 (unused) ; tested wet

Front (27) Back (26)

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno.


Roundno.


Roundno.


5 1174 a 4 1285a 3 1222 a 5 1313 a6 1238 a 7 1268 a 4 1252 a 7 1285 a

11 1172 a 8 1186 a 6 1282 a 8 1238 a12 1186 a 9 1248 a 9 1242 a 10 122213 1188a 10 1160 a 11 1288 a 13 1248 a

14 1232 a

aUsed to calculate ballistic limit.

35

Sample 32 (moderate wear) ; tested dry

Front Back

Partialpenetration

Completepenetration

Partialpenetration

Completepenetration

Roundno.


Roundno

.


Roundno.


Roundno.


4 1200 a 3 1266a 5 12 58 a 3 13185 12 68 a 6 1250 a 7 1248 a 4 12427 1232 a 8 12 61a 10 1245a 6 1290

11 12 15 a 9 12 15a 15 1227a 8 124212 12 10 a 10 1258a 20 1178 a 9 1232 a

12 1261a

13 126614 1235 a

16 124517 1224 a

18 1198 a

19 1192 a


36

NBS-114A (rev. 2-80

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATASHEET (See instructions)

1. PUBLICATION ORREPORT NO.NBSIR 86-3444

2. Performing Organ. Report No. 3. Publ ication Date

September 1986

4. TITLE AND SUBTITLE

Ballistic Tests of Used Soft Body Armor

5. AUTHOR(S)Daniel E. Frank; 702

6. PERFORMING ORGANIZATION (If joint or other than NBS. see instructions)

national bureau of standardsDEPARTMENT OF COMMERCEWASHINGTON, D.C. 20234

7. Contract/Grant No.

8. Type of Report & Period Covered

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City. State. ZIP)

National Institute of JusticeU.S. Department of JusticeWashington, DC 20531

10. SUPPLEMENTARY NOTES

| |

Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significantbi bliography or literature survey, mention it here)

A sample of 24 ballistic resistant undergarments (soft bodyarmor) from a production lot of 1500 originally distributed to 15police departments throughout the United States in 1975 for issue toofficers as part of a Law Enforcement Assistance Administrationdemonstration project, was tested for V5Q ballistic limit. Theprogram was a joint effort of the U.S. Department of Justice NationalInstitute of Justice and the National Research Council of CanadaPublic Safety Project Office. Tests of ballistic limit were conductedon virgin armor that were never issued, and armor showing evidence oflight, moderate, and heavy wear both dry and while wet. The resultsshow that armor does not lose ballistic efficiency as a consequence ofage

.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s)

ballistic limit; ballistic-resistant body armor; ballistic testing;body armor; Kevlar; soft body armor

13. AVAILABILITY

[yl Unlimited

| |

For Official Distribution. Do Not Release to NTIS~~1 Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

(XJ Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OFPRINTED PAGES

44

15. Price

$9.95USCOMM-DC 6043-P80

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